Man wins $7m for popcorn lung

A US man who was diagnosed with "popcorn lung", possibly from inhaling the artificial butter smell of the microwave popcorn he regularly ate, has won a $US7.2 million ($A6.9 million) lawsuit against several food companies.

Wayne Watson's lawyer, Ken McClain, said a federal jury granted the sum on Wednesday against Gilster-Mary Lee, The Kroger and Dillon companies.

Watson, of Denver, developed respiratory problems in 2007.

He previously settled claims against the flavour developer, FONA International, formerly Flavors of North America.

Watson, 59, argued that the companies did not warn consumers that inhaling the buttery aroma could put them at risk of lung injury.

Defence lawyers had argued that Watson's health problems stemmed not from popcorn but from his years of working with carpet-cleaning chemicals.